16956561691 has 16 divisors (see below), whose sum is σ = 17760142080. Its totient is φ = 16169448960.

The previous prime is 16956561689. The next prime is 16956561697. The reversal of 16956561691 is 19616565961.

It is a cyclic number.

It is not a de Polignac number, because 16956561691 - 2¹ = 16956561689 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (16956561697) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2914101 + ... + 2919913.

It is an arithmetic number, because the mean of its divisors is an integer number (1110008880).

Almost surely, 2^16956561691 is an apocalyptic number.

16956561691 is a deficient number, since it is larger than the sum of its proper divisors (803580389).

16956561691 is a wasteful number, since it uses less digits than its factorization.

16956561691 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7206.

The product of its digits is 2624400, while the sum is 55.

The spelling of 16956561691 in words is "sixteen billion, nine hundred fifty-six million, five hundred sixty-one thousand, six hundred ninety-one".